I probably should have thought about it a little more before posting...
All I really need is an smtp client to send the alert even if postfix dies. It looks like monit has one built-in anyhow, so there's no problem to solve...
I agree with you, Chris - if it's not necessary, don't run it

I was really only curious if there was one available already for other reasons. Actually I'm glad there's little else on the linodes
Thanks for the generous offer dmuench, though I think it won't be needed after all. BTW I'm on host9 (at Hurricane Electric).
Thanks,
Paul